1. Field of the Invention
The present invention is directed to novel cyclopropane compounds and, more specifically, to 2-vinyl and 2-ethylcyclopropane compounds having a single carboxylate moiety present on the ring. The compounds of this invention are useful as chemical intermediates, pesticides, insecticides and as fragrance chemicals.
2. Discussion of the Prior Art
Pyrethrin and various synthetic compounds modeled thereafter, such as allethrin, are well known and while primarily recognized for their insecticidal properties are also useful for a variety of other applications. In view of the diverse physical and chemical properties possible with such products, much effort has been directed to the synthesis of other structurally related compounds, i.e., based on the cyclopropane structure.
Various cyclopropane monocarboxylate compounds have been prepared, however, most of these reported compounds have substituents other than hydrogen at the three ring positions. For example, in U.S. Pat. No. 4,180,446 dihalogen vinylcyclopropanecarboxylic acid esters of the formula ##STR1## where R is an alkyl moiety and X is chlorine or bromine are obtained by a photochemical ring contraction of a correspondingly substituted dihydrofuran compound. Cyclopropane compounds useful as pesticides or pesticide intermediates and having the formula ##STR2## wherein Y and Z each independently is oxygen or sulfur and X is chlorine, bromine or OR in which R is hydrogen, a salt-forming cation, an alkyl group or residues of certain other alcohols have also been disclosed in U.S. Pat. No. 4,225,612.
Cyclopropane monocarboxylate compounds having only two of the ring positions substituted have been reported by Kierstead et al. (J. Chem. Soc., 1953, 1799-1803). Kierstead et al. prepared ethyl 1-acetyl-2-vinylcyclopropane-1-carboxylate by the condensation of ethyl sodioacetoacetate with 1,4-dibromobutene-2. The ability to obtain other related compounds was restricted, however, due to the limitations of the condensation reaction employed by Kierstead et al.